This invention is directed to transesophageal echocardiography (TEE) probes used for imaging human organs, particularly the heart. TEE probes are well known in the art and comprise an ultrasonic transducer mounted at the end of a semi-flexible endoscope. The endoscope typically has an articulation section at its distal end that allows the operator to rotate or move the distal end of the endoscope such that the ultrasonic transducer is optimally positioned for imaging the relevant organ. Movement of the articulation section is effected in a controlled manner through mechanical controls (e.g., handles or knobs) positioned on a handle located on the proximal end of the endoscope.
In prior TEE probes, the semi-flexible nature of the endoscope enabled physicians or clinicians to introduce the ultrasonic transducer through the esophagus of a patient to a position where the heart or other relevant structure could be ultrasonically imaged. This was particularly useful during open-heart surgery, when conventional ultrasonic imaging was impractical due to the existence of an open chest cavity. In addition, TEE probes were useful when obesity or other anatomical anomalies precluded the use of conventional ultrasonic imaging. However, because of their uniform stiffness, introducing prior TEE probes into the esophagus was difficult and required significant clinical skill because of the variations in esophageal anatomy. Also, once introduced, there was no means for changing the stiffness characteristics of the TEE probe.
Therefore, there is a need for a TEE probe with variable stiffness characteristics that address these prior problems.
In a preferred embodiment of the invention, a transesophageal probe with variable stiffness includes an endoscope with a probe head connected to a distal end of the endoscope. A flexible tube is secured to the endoscope and has a semi-rigid rod slidably disposed within the flexible tube.
In an alternative embodiment of the invention, a transesophageal probe with variable stiffness includes an endoscope having an articulation section. The endoscope has a probe head connected to its distal end. A flexible tube is secured within the interior of the endoscope. A semi-rigid rod is slidably disposed within the flexible tube.
The preferred embodiment has a number of advantages. In particular, the semi-rigid rod can be advanced or retracted by an operator to vary the stiffness of the endoscope. This configuration permits the operator to vary the stiffness of the endoscope in order to better accommodate variations in anatomy, particularly esophageal anatomy. Use of different structure for the flexible tube (e.g., a helical structure) or different materials for the semi-rigid rod (e.g., metal) permit additional variations in the stiffness characteristics of the transesophageal probe. Other features and advantages of the invention will become apparent from the description that follows.